Proteomic analysis of the molecular mechanisms of the response of plant seeds to pre-sowing treatment by stressors

Abstract

Seed treatment with non-ionizing low-level radiation (NR), suchas cold plasma (CP) or electromagnetic field (EF), is a moderneco-agricultural technology for stimulation of plant germinationand performance. The molecular determinants of seed responseto these treatments are not established and no genomic studies ofplant seed response to NR have been reported. We studied theeffects of pre-sowing seed treatment, using vacuum (7 min),radio-frequency EF (5–15 min) and CP (2–7 min), on germina-tion and growth of non-oilseed Helianthus annuus. To gain aninsight into the molecular mechanisms underlying effect of NRon sunflower seed germination and dormancy, we estimatedchanges induced in the balance of plant hormones and differen-tial protein expression. The results of the germination tests andestimation of seedling morphology showed that response devel-ops in time and is stronger when sowing is performed in 7 days in comparison to 3 days after seed treatment. The 2D DIGEanalysis revealed 38 differentially expressed proteoforms in ker-nels of seeds treated with CP or EF. Proteins involved in biologi-cal processes of seed maturation, response to stress, response toabscisic acid stimulus, processes of organonitrogen compoundmetabolism and glucose catabolism were identified. While expres-sion patterns for majority of the proteins were highly specific toCP and EF treated seed kernels, accumulation of several proteo-forms of seed storage proteins (SSP), including vincilin-like, mira-culin-like protein and albumin-8 were common for bothexperimental groups. This suggested that response to NR treat-ment could be at least partially associated to function of SSPs inresponse to oxidative stress that protects proteins required forseed germination and seedling formation. [...]